Fuse for gyrating and non-gyrating projectiles



May 16, 1961 P. cETRE 2,984,184

FUSE FOR GYRATING AND NONGYRATING PROJECTILES Filed March 24, 1958 3 Sheets-Sheet 1 May 16, 1961 P. CETRE 2,984,184

FUSE FOR GYRATING AND NON-GYRATING PROJECTILES Filed March 24, 1958 5 SheetsSheet 2 A TT'Y May 16, 1961 P. CFITRE 2,

FUSE FOR GYRATING AND NON-GYRATING PROJECTILES Filed March 24, 1958 3 Sheets-Sheet 3 Paw/e5 (Fr/Pf z/TTM FOR GYRATING AND NON-GYRATING PROJECTILES Pierre Ctre, deceased, late of Ave. Giuseppe Motta 26, Geneva, Switzerland, by Jeanne Marie Louise Ctre, adminisnatrix, Geneva, Switzerland Filed Mar. 24, 1958, Ser. No. 723,221

Claims priority, application Switzerland Mar. 28, 1957 3 Claims. (Cl. 102-74) At the present time, there exist fuzes for gyrating and non-gyrating projectiles which comprise a firing and trajectory safety device operated at the moment of the shot by the displacement of an inertia mass.

The fuze, which is the object of this invention, differs from known fuzes in that it comprises a security device and a locking device retaining, against the action of a spring, a closing member in a safety position, and in that after a specified period of operation, the firing safety device not only is no longer opposed to the firing of a primary primer upon an impact, but further causes the releasing of the security device and the actuation of the closing member by said spring until one of two positions in which the said closing member is no longer opposed to the transmission of the fire of the primary primer.

The annexed drawing shows diagrammatically and by way of example an embodiment of the fuze as well as varied embodiments of a blocking device for the lock of the clockwork escapement.

Fig. 1 is an axial sectional view, the elements of the fuze being in the safety position.

Fig. 2 is a partial sectional view, on a smaller scale, along line IIII of Fig. 1.

Fig. 3 is a partial sectional View on a small scale and along line IIIIII of Fig. 1, the firing safety device being in the safety position.

Fig. 4 is a plan view of the security device, its elements being in the safety position.

Fig. 5 is a plan view of the security device, its elements being in the position of delayed firing.

Fig. 6 is a plan view of the security device, its elements being in the position of instantaneous firing.

Fig. 7 is a partial sectional view along line VIIVII of Fig. 6.

Fig. 8 is a partial sectional view, on a large scale, of a variant of a device for blocking the lock of the clockwork escapement.

Fig. 9 is a sectional view of another variant of the device for blocking the lock of the clockwork escapement.

According to Figs. 1 to 7 of the annexed drawing given by way of example, the fuze comprises a cap 1, in which is mounted a firing safety device actuated by a clockwork mechanism. The said clockwork mechanism comprises a toothed member 2 sliding in a guide 3 and subjected to the action of a driving spring 4. The set of teeth 5 of the said member 2 is connected by pinions e 2 and e to a toothed wheel e, which co-operates with a notch b of a balance-wheel b. The said balancewheel is normally immobilized by a pin 6 sliding in a guide 7 and carried by an inertia mass 8 which may slide, under the action of a high acceleration to which the fuze may be subjected, in a housing 9 against the action of a return-spring 10.

The toothed member 2 is provided with an aperture 11 having the shape of a keyhole through which passes a striking pin 12 provided with a shoulder 13, the diameter of which is larger than the narrow part 14 of the States atent ree aperture 11, but smaller than the enlarged part 15 of the latter.

The end of the striking pin 12 fits into a bore 16 in the head 17 of a primer carrier 18 which may slide in a housing 19. The head 17 of the primer carrier has a diameter substantially equal to that of the shoulder of the striking pin, so that the said head cannot engage in the narrow part 14 of the aperture 11, but may, on the other hand, penetrate into the enlarged part 15 of the latter.

The operation of the firing and trajectory safety device described above and by way of example is the following:

Upon the firing of the projectile, the high acceleration to which the fuze is subjected causes a displacement of the inertia mass 8 against the action of its return-spring 10. The pin 6 comes out of its guide 7 and then is held in a withdrawn position by the elasticity of its arms, which spread and prevent it from penetrating afresh into its guide, under the action of the return-spring 10.

The balance-wheel b being released, the driving spring 4 actuates the toothed member 2 towards the right of Fig. 1, at a speed determined by the clockwork.mechanism. After a certain period of time, the said member 2 abuts the end wall 20 of its guide 3.

In this position of the toothed member 2, the enlarged part 15 of the aperture 11 is coaxial with the striking pin 12 (Fig. 3). Thus, from this moment, the safety device no longer prevents firing so that upon an impact, the part 13 of striking pin passes through opening 15 and the pin penetrates into the primary primer 21 and brings about its firing.

The said firing and trajectory safety device has been here described merely with a view to rendering more understandable the operation of the safety device, but it is to be understood that the said firing safety device could be replaced by any other known firing safety device.

The security device comprises a cylindrical support 22, provided with a delay cap 23 and a bore 24 for the instantaneous firing.

The said support 22 has a housing 25 in which is housed a plate 26 carrying a detonator 27. The said plate carries an axle 28 rotating in bearings 29 and 30, provided in the support 22 and in a mounting plate 31 secured in a hollow 32 of the support 22. The said axle 28 is subjected to the action of a spring 33 coaxial with the said axle and of which one end is engaged in a slot 34, made in the said axle, while its other end is engaged in a slot 35 (Fig. 4) made in the support 22.

In a hollow 36 of the support 22 is housed a closing member 37 carried along in the angular displacements of'the axle 28. To this end, the closing member is provided with a non-circular boring, engaged on a part 38 of the axle 28 which has a cross section of corresponding shape. A blocking device holds, against the action of the spring 33, the security device in a position in which the detonator and the closing member 37 are each located in a safety position. The said blocking device comprises a catch 39 carried by the closing member 37. The said catch is provided with a conical end extending through an arcuate aperture 40 formed in the mounting plate 31. In the safety position of the device (position shown in Figs. 1 and 4), the catch 39 bears, under the action of the spring 33, on a conical orifice 41 disposed in the rear end of the primer carrier 18.

When, after the firing of the projectile and after a period specified by the clockwork mechanism, the toothed member 2 of the firing safety device reaches its position determined by the wall 20 in which it no longer prevents a relative displacement between the primer carrier 18 and the striking pin 12, the thrust exerted by the spring 33 on Patented May 16, 1961 the closing member produces a sliding of the two conical surfaces 39 and 41 one with resp ct to the other, because the primer carrier 18 may now be moved upwards, its head being able to penetrate into the enlarged part 15 of the keyhole shaped aperture, made in the toothed member Thus, the said catch 39 escapes from the conical orifice 41 and the freed closing member is moved by the spring 33 in the direction of the arrow 1, The said closing member carries along the plate 26 in its movement, in order to bring, as described hereafter, the detonator 27 into one of its active positions and the closing member into one of the two positions in which it no longer resists the transmission of the fire of the primary primer 21. p p

' The cap 1 is provided with a control member 42 accessible from the exterior and which carries an abutment 43, movable between an active position (Figs. 1 and 7) determined by the edge 44 of a notch (Fig. 4) formed in the mounting plate 31 and a withdrawn position (shown in dash lines in Fig. 7) determined by the upper face of the said mounting plate 31.

When the said abutment 43 is in the active position (Figs. 1 and 7), it is located in the path of a stop face 45 carried by the closing member 37 so that the freed closing member displaces and comes to occupy the position shown in Fig. and in which the detonator 27 is located opposite the delay cap 23 while the closing member 37 uncovers the said delay cap. Thus, upon impact, the primary primer 21 fired by the striking pin 12, brings about the firing of the detonator 27 by means of the de= lay cap 23. Indeed, as shown in Fig. 5, when the stop face 45 bears against the abutment 43, the rear edge 58 of the closure device uncovers the end 59 of the aperture 40, but the bore 24 remains covered by the said closing member. Thus, the fire of the primer 21 passing through the end of the aperture 40 and between the mounting plate 31 and the bottom 61 of the hollow 36 may reach the delay cap 23, but cannot reach the bore 24.

On the other hand, when the abutment 43 is in the withdrawn position, the closing member 37 is moved by its spring 33 until the catch 39 abuts against the end 47 of the aperture 40 (Fig. 6) formed in the mounting plate. The latter is held against any angular movement by a tongue 48 engaged in a notch 49 made in the support 22. When the catch 39 bears against the end 47 of the aperture 40, the detonator 27 carried by the plate 26 which is angularly fixed with the closing member 37 is located opposite the bore 24 made in the support 22, whereas the closing member uncovers the said bore. Thus, upon impact, the firing of the primary primer 21' by the striking pin 12 induces directly, through the said bore 24, the firing of the detonator 27. Thus, by means of a simple plane closing member 37 which uncovers either a delay cap or the said delay primer and a bore, it is possible very readily to produce either the delayed firing or the instantaneous firing of the detonator.

The support 22 also comprises a recess 50*, situated above the detonator 27, located in the safety position (Fig. Thus, if through the influence for example, of a chemical agent or other fortuitous cause, the said detonator were fired ill-timely, while in the safety position, the thin wall 51 of the support 22 tears under the effect of the pressure of the gases produced and these may spread inside the cap, but cannot, in any case, bring about the initiation of the explosive charge 60.

The support 22 is held in position in a housing by means of a plug 52 which is provided, in its central part, with a blind bore '53. Upon the combustion of the detonator situated in one of its active positions (opposite the delay cap 23 or the bore 24), the thin wall 54 forming the bottom of the said bore 53 is broken down by the pressure of the developed gases and the "explosive charge 60 is initiated. The said wall 54 is 4 however of sufficient thickness to prevent any passage of gas towards the explosive charge 60 in the event of an ill-timed explosion of the said detonator 27 while the same is in the safety position.

The said wall 54 completely" separates the mechanical members mounted in the cap from the explosive charge, so that the movements of the said mechanical members cannot be hindered by dust emanatin from the explosive charge,- for example.

So as to prevent any possibility of an ill-timed setting in operation of the firing and trajectory safety device, for example during transport or parachut-ing of the projectile, the fuze may also be provided with a locking device for the inertia mass 8 bringing about, upon the firing of the projectile, the operation of the said safety device. The said locking device is constituted, according to a variant shown in Fig. 9, by a pin 55 rotating free in a bore 57 made in the cap 1 approximately tangentially to the housing 9 of the inertia mass 8..

The said pin 55 carries an off center finger 56 whichmay occupy either a locki'ng position, in which it en= gages in a circular groove 66 formed in the inertia mass, or an unlocked position, in which the finger is com= plet'ely disengaged from the groove 66. In order to snow of locking and -unlockin at will the inertia mass 8, the pin 55 is provided with a control member (not shown) accessible from the exterior and similar to the eo t'rorrnember 42. I Fig. 8 shows another variant of the said locking device. The inertia mass 8 is provided with a circular groove '63, into which may penetrate a finger 64, carried by a pin '67 rotating in a radial guide 62 and provided with a control member (not shown) accessible from the exterior.

An embodiment of the fuze, forming the object of this invention, and two variants of the locking device preventing an ill-timed setting in operation of the firing safety device have been described herein by way of example and with reference to the annexed drawing, but it is obvious that many variants may be envisaged.

Thus, for example, the locking device of the security device may include a pin parallel to the axis of the fuie and of which the lower conical end would engage in a conical impression of the closing member, while its upper end would be in contact with the lower face of the toothed member 2 In such a case, the release of the security device could be brought about when the toothed member 2 bears against the wall 20 through the penetration, under the action of the spring 33, of the upper end of the said pin in the narrow part 14 of the keyholeshaped aperture. I The firing safety device described couldbe replaced by any known device preventing the firing during a certain specified period after the firing of the projectile. The said device could comprise a known clockwork mechanism, such as the one described with reference to the annexed drawing or any other known device. The driving spring 4 may be loaded when the fuze is assembled as in the example described, or, on the contrary, be loaded upon firing of the projectile, by an inertia mass.

In another variant of the described fuze, in the case for example, in which the explosive charge 60 is such that'the same may be initiated by the firing of the primary primer 21, the plate 26 carrying the detonator 27 may be suppressed. The security device then comprising only the closing member 37 subjected to the action of -the spring 33 and held in the safety position, that is to say of closure of the relay 23 and of the bore 24, 'bythe locking device the release of which is brought about by the movemeht of a member of the firing safet device.

What is claimed is: V i

1-. I a fu'z'e of g r-atihg and non'gyrating projectiles comprising a. cap,- a primer ear r ie'r coax'ially mounted with respect to said cap, a primer carried by said primer carrier, a firing pin coaxially mounted with respect to said primer carrier, said primer carrier and said firing pin being housed in said cap and both slidably mounted therein to enable said firing pin to engage said primer carrier and fire said primer located in said primer carrier, a shoulder provided on said firing pin, a locking member interposed between said shoulder and the front face of said primer carrier to prevent relative movement of said firing pin and said primer carrier against one another, a clockwork, a mechanical connection com prising pinions and gears connecting said clockwork to said locking member for shifting said locking member from an operative or safe position into an inoperative or fire position, whereby when in said fire position said locking member frees said firing pin and said primer carrier in order to enable them to move one against the other upon impact of the projectile, an inertia mass, a pin mounted on said inertia mass, first spring means maintaining said pin in a locking position for which said clockwork is maintained in rest position, said inertia mass actuated upon firing against the action of said spring means, freeing said clockwork, a plug closing the rear face of said cap of said fuse, the combination of a support located rearwardly of and adjacent to said primer carrier, two adjacent spaced fire passages made in said support, said two fire passages extending rearwardly therethrough, a shaft pivoted in and extending coaxially through said support, a second spring means acting on said shaft to cause its angular displacements, a closing member located in front of the forward end of said support and drivingly connected to said shaft to move therewith from a rest position for which said closing member covers both said fire passages to a first and a second working position for which said closing member uncovers one and both of said fire passages respectively, a plate located adjacent the rear end of said support and also drivingly connected to said shaft to rotate with said shaft and said closing member, a housing made in said plate, a detonator located in said housing, a locking device comprising abutting means carried by said closing member and means carried by said primer carrier cooperating one with the other for maintaining said closing member in its rest position until said locking member has been shifted by said clockwork to its fire position to free said primer carrier, said second spring means displacing angularly said shaft, said closing member and said plate, a hand-operated member accessible from the outside of said cap of said fuze, abutment means carried by said hand-operated member, stop means located on the periphery of said closing member, said abutment means and said stop means cooperating one with the other to define said first and said second Working positions of said closing member, said shaft and said plate, corresponding to different angular position of said hand-operated member, whereby said detonator of said plate is in alignment with one of said two fire passages of said support when said shaft is in its first working position and with the other of said two fire passages when said shaft is in its second working position, said first and said second working positions corresponding, upon impact of said projectile, to a delayed firing by means of said delay cap and to an instantaneous firing of said projectile.

2. In a fuze for gyrating and nongyrating projectiles comprising a primary primer, a striking pin, abutment means carried by said striking pin, a locking member displaceable from a safe position to a fire position and interposed between said abutment means of said striking pin and said primary primer, a clockwork mechanical driving means connecting said clockwork to said locking member, an inertia mass, a pin mounted on said inertia mass, spring means maintaining said pin in locking position of said clockwork, firing of said primer freeing said clockwork by axial displacement of said inertia mass against the action of said spring means, said clockwork controlling the displacement of said locking member from said safe position to said fire position, a closing member, a locking device of said closing member means carried by said primary primer, the combination of an angularly displaceable shaft drivingly connected to said closing member, a spring acting on said shaft to cause its angular displacements, said closing member being maintained in a rest positionagainst said spring by said locking device until said locking member has been shifted into its fire position, a support mounted adjacent and parallel to said closing member, a first and a second orifice in said support closed on one side by said closing member when said closing member is in rest position, a delay cap located in said first orifice of said support, a plate mounted on the other side of said support, a housing provided in said plate, a detonator located in said housing, said shaft extending coaxially through and pivoted in said support and drivingly connected further to said plate, a hand-operated member accessible from the outside of said fuze, abutment means carried by said hand-operated member and displaceable from a rest to a working position through angular displacement of said hand-operated member, stop means located on the pe n'phery of said closing member, whereby for a firstangular position of said hand-operated member said shaft is rotated by means of said spring from its rest position to a first working position defined by the abutment of said abutment means on said stop means for which said first orifice containing said delay cap is uncovered by said closing member and said detonator carried by said plate is in alignment with said first orifice of said support, said first working position corresponding to the delay firing of said projectile upon impact, and for a second angular position of said hand-operated member said shaft is rotated by means of said spring from its rest position to a second working position, said stop means of said closing member having passed said abtument means of said hand-operated member, for which said second orifice of said support is uncovered by said closing member and said detonator carried by said plate is in alignment with said second orifice, said second working position corresponding to the instantaneous firing of said projectile upon impact.

3. A fuze according to claim 1 in which a projection is carried by said closing member, said projection extending perpendicularly to said closing member, a conical portion located at the forward end of said projection, a conical recess for engaging said projection carried by the rear portion of said primer carrier, said projection and said conical recess abutting one against the other to define the rest position of said closing member when said locking member is in its safe position, said projection escaping said conical recess under the action of said spring when said locking member is in its fire position by lifting said primer carrier.

References Cited in the file of this patent UNITED STATES PATENTS 1,751,616 Brayton Mar. 25, 1930 1,863,888 Varaud June 21, 1932 2,129,692 Hottinger Sept. 13, 1938 2,183,073 Honger Dec. 12, 1939 2,511,872 Parker June 20, 1950 2,664,822 Hale Jan. 5, 1954 2,821,925 Varaud, Feb. 4, 1958 2,825,284 Kuhn Mar. 4, 1958 

